The Cron Job/Crontab
To have your task run at this frequency, use the following cron:
0 11 */3 * *
This cron command translates to the following (in Human-Readable format):
“Every 3 days at 11:00 am.”
What is a Cron Job & Crontab?
A cron job is a time-based task that is set to run at specific intervals. These jobs are usually used for maintenance or automation purposes. For example, a cron job could be set to delete temporary files every week so that they don’t take up space on the server.
To create or edit a cron job, users must first open the crontab file using a text editor. The crontab file contains instructions for the cron daemon, which is the program that actually executes the commands specified in the file. Each line in the crontab file represents a single task or command.
Every cron job uses five fields. Here is an explanation of what each field does in this cron, which runs “every 3 days at 11:00 am“:
FUN FACT: If you want to see what commands are scheduled in your crontab, type: “crontab -l”.
You might want to set up a crontab or cron job to run every 3 days at 11:00 am for several reasons, including:
- A daily backup that needs to be run every 3 days
- Running a script that checks for updates to a software repository
- Generating reports that need to be sent out every 3 days
- Checking for expired SSL certificates
Similar Cron Jobs
You might also want to run a crontab:
- every 8 days
- every 1 day
- every 4 days
- every 5 days
- every 6 days
- every 3 days
- every 9 days at 11:00 pm
- every 3 days at 4:30 pm
FUN FACT: If you need to temporarily disable a cron job, you can simply comment out the line in the crontab file that corresponds to that particular task..
In this article, you learned how to set up a cron job that runs every 3 days at 11:00 am. Please share this page with friends and colleagues if you find it useful.
If you have any questions, please don’t hesitate to comment below.
If you are looking for cron jobs that run at certain minutes, hours, days, weekdays, or months, or if you are looking for miscellaneous cron jobs, then check out our relevant sections, or visit our cron job cheat sheet for a list of hundreds of popular cron jobs.